PRODUCTION OF A LACTOBACILLUS-PLANTARUM STARTER WITH LINAMARASE AND AMYLASE ACTIVITIES FOR CASSAVA FERMENTATION

Lactobacillus plantarum strain A6 isolated from cassava, cultured on cellobiose MRS medium showed a growth rate of 0.41 h-1, a biomass yield of 0.22 g g-1, and produced simultaneously an intracellular linamarase (76.4 U g-1 of biomass) and an extracellular amylase (36 U ml-1). The synthesis of both enzymes was repressed by glucose. The use of such a strain as a cassava fermentation starter for gari production had the following influences: a change from a hetero-fermentative pattern observed in natural fermentation to a homofermentation, a lower final pH, a faster pH decline rate and a greater production of lactic acid (50 g kg-1 DM). However. this starter did not appear to play a significant role in cassava detoxification, since it was observed that the level of endogenous linamarase released during the grating of the roots was sufficient to permit the complete and rapid breakdown of linamarin.